Method and apparatus for controlling coverage of wireless transceiver

ABSTRACT

A method of controlling coverage of a wireless transceiver, including receiving information about the wireless transceiver from an external device, and changing a coverage value of the wireless transceiver, which has been set in advance, based on the received information about the wireless transceiver.

PRIORITY

This application claims priority to Korean Patent Application No.10-2011-0101436, filed on Oct. 5, 2011, in the Korean IntellectualProperty Office, the contents of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a method and apparatus forcontrolling coverage of a wireless transceiver, and more particularly,to a method and apparatus for controlling coverage of a wirelesstransceiver based on the strength of a signal transmitted by thewireless transceiver.

2. Description of the Related Art

A wireless Local Area Network (LAN), which is typically referred to asWi-Fi, is used within a predetermined distance from installed accesspoints, or wireless transceivers, to provide a wireless communicationservice.

In view of the worldwide increase in sales of mobile devices that handlelarge amounts of traffic, such as smartphones, tablet Personal Computers(PCs), and mobile PCs, shipments of Wi-Fi devices significantly increaseevery year. Following this trend is the increased installation ofwireless access points or wireless transceivers for transmitting a Wi-Fiwireless signal, such as a beacon. However, there is a need in the artto control coverage of beacons to accurately define a zone where a Wi-Filocal service is provided.

SUMMARY OF THE INVENTION

The present invention provides a method and apparatus for controllingcoverage of a wireless transceiver, wherein the coverage is accuratelycontrolled by an external apparatus, such as a server, and for updatingthe coverage based on the strength of a signal transmitted by thewireless transceiver.

According to an aspect of the present invention, there is provided amethod of controlling coverage of a wireless transceiver, includingreceiving information about the wireless transceiver from an externaldevice, and changing a coverage value of the wireless transceiver thathas been set in advance, based on the received information about thewireless transceiver.

According to another aspect of the present invention, there is providedan apparatus for controlling coverage of a wireless transceiver,including a communication unit that receives information about thewireless transceiver from an external device, and a control unit thatchanges a coverage value of the wireless transceiver based on thereceived information about the wireless transceiver.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become more apparent by describing in detail embodiments thereofwith reference to the attached drawings in which:

FIG. 1 illustrates a location-based service supply system according toan embodiment of the present invention;

FIG. 2 illustrates a method of providing a near field service by awireless transceiver, according to an embodiment of the presentinvention;

FIG. 3 illustrates a critical received signal strength table accordingto an embodiment of the present invention;

FIG. 4 illustrates a method of controlling coverage of a wirelesstransceiver, according to an embodiment of the present invention;

FIG. 5 illustrates a method of changing coverage of a wirelesstransceiver, according to an embodiment of the present invention;

FIGS. 6A and 6B illustrate changed coverage of a wireless transceiver,according to embodiments of the present invention; and

FIG. 7 illustrates a coverage change device of a wireless transceiver,according to an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Embodiments of the present invention will now be described in detailwith reference to the attached drawings. Those of ordinary skill in theart will recognize that various changes and modifications of theembodiments described herein can be made without departing from thescope and spirit of the invention. Also, descriptions of well-knownfunctions and constructions are omitted for the sake of clarity andconciseness.

FIG. 1 illustrates a location-based service supply system according toan embodiment of the present invention.

The location-based service supply system includes a terminal 110 and aserver 120. The terminal 110 includes a positioning 111 module and amobile communication 112 module, and the server 120 includes a platform121 and an application 122. In the current embodiment, the structure ofeach of these components is just an example, and the present inventionis not limited thereto.

The positioning 111 module performs location verification of theterminal 110 and uses triangulation, such as cell ID, enhanced cell ID,Angle of Arrival (AoA), Time of Arrival (ToA), Time Difference ofArrival (TDoA), Global Positioning System (GPS), Assisted GPS (AGPS),Differential GPS (DGPS), or WiFi.

The mobile communication 112 module performs communication between theterminal 110 and the server 120. Examples of a mobilecommunication-related technology are Code Division Multiple Access(CDMA), Global System for Mobile communications (GSM), Time DivisionMultiple Access (TDMA), and Personal Communication Service (PCS).Examples of a near field communication related technology are WiFi andBluetooth®.

The platform 121 may include server architecture, storage, indexing,open Application Programming Interface (API), and security. The serverarchitecture technology refers to a location-based processing technologythat corresponds to a location-based function, such as obtaining of alocation from a location-obtaining server and responding to a locationinformation request of the terminal side 110 (client), managing oflocation information and processing of location information regarding anindividual or a group, and tracing of a movement path.

The storage technology is for storing and managing information with alarge capacity. The indexing technology is for organizing locationinformation or information regarding the location information in anoptimized form and constituting the information for ease of search. Theopen API technology enables websites to interact with each other byproviding location information and information regarding the locationinformation. The security technology is for controlling user access,such as user profile management, authorization, and security.

The application 122 is for finally providing a location-based service tothe terminal side 110. Examples of the application 122 include map,navigation, information, commerce, health care, tracing, advertising,entertainment, health and safety.

FIG. 2 illustrates a method of providing a near field service by awireless transceiver, according to an embodiment of the presentinvention.

Referring to FIG. 2, in step 210, a terminal receives signalstransmitted by at least one wireless transceiver, where wirelesstransceivers broadcast the same transmission signal strength. Thewireless transceiver may be a beacon or an AP. The transmission signalsof the wireless transceiver may include MAC address information asunique information, a Service Set Identifier (SSID) or a Basic ServiceSet Identifier (BSSID).

In step 220, the terminal measures the strength of a signal transmittedby a wireless transceiver. When the terminal receives a signaltransmitted by the wireless transceiver, the terminal detects a ReceivedSignal Strength Indication (RSSI), which is the strength of the signalreceived.

In step 230, the terminal compares the measured received signal strengthwith a critical received signal strength that has been stored inadvance. The critical received signal strength may have been alreadystored by using an external apparatus, such as an external server. Thecritical received signal strength refers to a critical value that isused as a reference that is considered in determining that the terminalis near the wireless transceiver. Identifying a wireless transceiverthat has transmitted the signal received as a reference for comparisonmay be executed based on a MAC address as unique information of thewireless transceiver or BSSID.

The remainder of the description of FIG. 2 will be given after thedescription of FIG. 3, which illustrates a critical received signalstrength table 300 according to an embodiment of the present invention.

Referring to FIG. 3, the critical received signal strength table 300includes beacon identification information 310, a MAC address 320, and acritical received signal strength 330. A decibel miliwatt (dBm) is aunit of the critical received signal strength 330. For example, when aterminal receives a signal transmitted by a beacon that has a MACaddress of 00:25:xx:xx:xx:x1, the terminal detects a received signalstrength of the transmission signal, extracts the MAC address00:25:xx:xx:xx:x1, and compares a critical received signal strength of−50 dBm with the detected signal received signal strength.

Returning to the description of FIG. 2, in step 240, the terminaldetermines whether the measured received signal strength is equal to orgreater than the critical received signal strength, and if the measuredreceived signal strength is equal to or greater than the criticalreceived signal strength, step 250 is performed. For example, referringto FIG. 3, if a measured received signal strength of a signaltransmitted by a beacon that has a MAC address of 00:25:xx:xx:xx:x1 is−40 dBm, the received signal strength is greater than the criticalsignal strength that is −50 dBm.

In step 250 of FIG. 2, when the measured received signal strength isequal to or greater than the critical received signal strength, theterminal determines that the wireless transceiver is nearby. Forexample, referring to FIG. 3, if a measured received signal strength ofa transmission signal from a beacon that has a MAC address of00:25:xx:xx:xx:x1 is −40 dBm, the received signal strength is greaterthan the critical signal strength that is −50 dBm and thus, the terminaldetermines that ap1 is nearby. Also, if the measured received signalstrength is less than the critical received signal strength, theterminal determines that a wireless transceiver that transmits thesignal received is not nearby.

FIG. 4 illustrates a method of controlling coverage of a wirelesstransceiver, according to an embodiment of the present invention.

Referring to FIG. 4, in step 410, a coverage control apparatus receivesinformation about a wireless transceiver from an external device, whichreceives a signal that is transmitted by a wireless transceiver, such asa beacon or an AP. A transmission signal of the wireless transceiver mayinclude MAC address information as unique information, and an SSID or aBSSID. Thereafter, the external device measures a received signalstrength of the transmission signal of the wireless transceiver. Whenthe external device receives a transmission signal from the wirelesstransceiver, the external device detects an RSSI of the received signal,and a location of the wireless transceiver.

For example, the external device may detect a location of the wirelesstransceiver by using GPS information, or by using a wireless transceiverthat is located near the external device. Thereafter, the externaldevice transmits unique information of the wireless transceiver includedin the signals transmitted by the wireless transceiver as informationabout the wireless transceiver and information about the detectionsignal strength to the coverage control apparatus. If the coveragecontrol apparatus does not have location information about the externaldevice, the external device may transmit the location information aboutthe external device together with information about the wirelesstransceiver to the coverage control apparatus.

In step 420, the coverage control apparatus may change a coverage valueof the wireless transceiver that has been stored in advance, based onthe received information about the wireless transceiver. The coveragevalue is of a distance within which a signal transmitted by the wirelesstransceiver has access to the external device. The coverage controlapparatus changes the coverage value of the wireless transceiver basedon the received unique information about the wireless transceiver andthe signal strength measured by the external device. If the coveragecontrol apparatus does not have the location information of the externaldevice, the coverage control apparatus changes the coverage value of thewireless transceiver based on the unique information of the wirelesstransceiver, the signal strength measured by the external device, andthe location information of the external device.

The coverage control apparatus may change a coverage region by changinga coverage value according to the signal strength measured by theexternal device at a location where the external device is placed. Forexample, if a received signal strength of the external device distancedfrom the wireless transceiver by 50 meters is −50 dBm and a referencesignal strength, which has been set in advance, is −60 dBm, the signalstrength of the wireless transceiver is stronger than the referencesignal strength. Thus, the coverage region is wider than a referencecoverage region. Accordingly, the coverage value is changed such thatthe previously set reference coverage region is widened. A coveragevalue corresponding to a reference coverage region is previouslydetermined.

FIG. 5 illustrates a method of changing coverage of a wirelesstransceiver, according to an embodiment of the present invention.

Referring to FIG. 5, in step 510, a coverage control apparatusdetermines, based on received information about the wirelesstransceiver, whether a coverage value of a wireless transceiver exists.That is, the coverage control apparatus determines whether a coveragevalue of the wireless transceiver corresponding to unique informationabout the wireless transceiver exists. When the coverage value exists,step 530 is performed, and when the coverage value does not exist, step520 is performed.

In step 520, if the coverage value of the wireless transceiver does notexist, the coverage control apparatus determines a coverage regionaccording to measured signal strength and generates a correspondingcoverage value. Then, step 530 is performed.

In step 530, the coverage control apparatus changes the coverage valueaccording to the strength of a signal transmitted by the wirelesstransceiver in such a manner that a coverage region of the wirelesstransceiver does not overlap with a coverage region of another wirelesstransceiver. The coverage control apparatus may compare the strength ofa signal transmitted by the wireless transceiver that has been measuredby the external device with a previously set reference signal strengthand may change the coverage value correspondingly.

For example, when the strength of the signal transmitted by the wirelesstransceiver, which has been measured at a location where the externaldevice is currently positioned, is smaller than the previously setreference signal strength, a coverage region is substantially smallerthan a previously set reference coverage region. Thus, the referencecoverage region needs to be reduced. That is, the coverage controlapparatus changes a coverage region according to the signal strengthdifference and changes a coverage value according to the changedcoverage region. The coverage control apparatus changes a coverage valuein such a manner that coverage regions of surrounding wirelesstransceivers do not overlap, to allow an external device to receive asignal transmitted by an appropriate wireless transceiver. According topolicy, a coverage value may be changed such that coverage regions ofsome wireless transceivers overlap with each other and other wirelesstransceivers do not overlap with each other.

If the coverage control apparatus generates a coverage value due toabsence of the coverage value of the wireless transceiver, it ispossible that the generated coverage region may overlap with a coverageregion of another wireless transceiver. In this case, the coveragecontrol apparatus may reset the coverage region to prevent overlappingin the same manner as described above, and may change a coverage valuein correspondence to the reset coverage region.

The remainder of the description of FIG. 5 will be given after thedescription of FIGS. 6A and 6B, which illustrate changed coverage of awireless transceiver, according to embodiments of the present invention.

FIG. 6A illustrates coverage regions according to strengths of signalsthat are transmitted by wireless transceivers AP1 601, AP2 602, and AP3603 and are received by a terminal 600. In FIG. 6A, the terminal 600 islocated in an overlapping region of the coverage regions.

In FIG. 6B, the coverage control apparatus changes a coverage value suchthat the coverage regions of the wireless transceivers AP1 601, AP2 602,and AP3 603 do not overlap with each other.

Returning to FIG. 5, in step 540, the coverage control apparatuscontrols signal strengths of the wireless transceivers AP1 601, AP2 602,and AP3 603 based on the changed coverage value. Each of the wirelesstransceivers AP1 601, AP2 602, and AP3 603 includes an interface capableof controlling a signal strength. The coverage control apparatus maytransmit information about the changed coverage value to the wirelesstransceivers AP1 601, AP2 602, and AP3 603 through an external device,or directly transmit the information to the wireless transceivers AP1601, AP2 602, and AP3 603. Thereafter, each of the wireless transceiversAP1 601, AP2 602, and AP3 603 controls a transmission signal strength incorrespondence to the changed coverage value.

FIG. 7 illustrates a coverage change device of a wireless transceiver,according to an embodiment of the present invention.

Hereinafter, an embodiment regarding a terminal to which a near fieldservice is provided by wireless transceivers 712 and 714 will bedescribed.

Referring to FIG. 7, the terminal is an external device 720. Theexternal device 720 receives signals transmitted by the wirelesstransceivers 712 and 714, which broadcast transmission signals havingthe same strength. The wireless transceivers 712 and 714 may each be abeacon or an AP. The transmission signals of the wireless transceivers712 and 714 may include MAC address information as unique information ofthe wireless transceivers 712 and 714, and an SSID or a BSSID.

The external device 720 measures strengths of the signals transmitted bythe wireless transceivers 712 and 714. When the external device 720receives the signals transmitted by the wireless transceivers 712 and714, the external device 720 detects an RSSI of a received transmissionsignal. Thereafter, the external device 720 compares the measuredreceived signal strength and a previously stored critical receivedsignal strength. The critical received signal strength may have beenalready stored by using an external apparatus, such as an externalserver. The critical received signal strength refers to a critical valuethat is used as a reference that is considered in determining whetherthe external device 720 is near the wireless transceivers 712 and 714.Identifying the wireless transceivers 712 and 714 that have transmittedthe signals received as a reference for comparison may be executed basedon a MAC address as unique information of the wireless transceiver orBSSID.

The external device 720 determines that the measured received signalstrength is equal to or greater than the critical received signalstrength, and in this case, the external device 720 determines that thewireless transceivers 712 and 714 are nearby. Also, when the measuredreceived signal strength is less than the critical received signalstrength, the external device 720 determines that the wirelesstransceivers 712 and 714 that have transmitted the signals are notnearby.

Hereinafter, a method of controlling coverage of the wirelesstransceivers 712 and 714 by a coverage control apparatus 730 will now bedescribed in detail.

A communication unit 732 receives information related to the wirelesstransceivers 712 and 714 from the external device 720, which receivessignals transmitted by the wireless transceivers 712 and 714, which area beacon or an AP. The transmission signals of the wireless transceivers712 and 714 may include MAC address information as unique information ofthe wireless transceivers 712 and 714, and an SSID or a BSSID.Thereafter, the external device 720 measures strengths of the signalstransmitted by the wireless transceivers 712 and 714.

When the external device 720 receives the signals transmitted by thewireless transceivers 712 and 714, the external device 720 detects anRSSI of a received transmission signal, as well as its' location, suchas by using GPS information or near field wireless transceivers 712 and714. The location detection method of the external device 720 may not belimited. Thereafter, the external device 720 may transmit uniqueinformation of the wireless transceivers 712 and 714 included in signalstransmitted by the wireless transceivers 712 and 714 as informationrelated to the wireless transceivers 712 and 714 and information aboutthe detection signal strength to the coverage control apparatus 730. Ifthe coverage control apparatus 730 does not have the locationinformation of the external device 720, the external device 720 maytransport the location information of the external device 720 togetherwith the information related to the wireless transceivers 712 and 714 tothe coverage control apparatus 730.

A control unit 734 changes a coverage value previously set for thewireless transceivers 712 and 714 based on the received informationabout the wireless transceivers 712 and 714. The coverage value is adistance within which a signal transmitted by the wireless transceivers712 and 714 has access to the external device 720. The control unit 734changes coverage values of the transceivers 712 and 714 based on thereceived unique information about the wireless transceivers 712 and 714and the signal strength measured by the external device 720. If astorage unit 736 does not have location information about the externaldevice 720, the control unit 734 changes coverage values of thetransceivers 712 and 714 based on the unique information about thewireless transceivers 712 and 714, the signal strength measured by theexternal device 720, and the location information of the external device720. The control unit 734 may change a coverage region by changing acoverage value according to a signal strength that is measured by theexternal device 720 where the external device 720 is located.

For example, if received signal strengths of the external device at adistance of 50 meters from the wireless transceivers 712 and 714 is −50dBm and a reference signal strength, which has been set in advance, is−60 dBm, the signal strengths of the wireless transceivers 712 and 714are stronger than the reference signal strength. Thus, the coverageregions are wider than a reference coverage region. Accordingly, thecoverage value is widened. A coverage value corresponding to a referencecoverage region is previously determined and stored in the storage unit736. The coverage value change is described in detail with reference toFIG. 5. A detailed method of changing coverage of the wirelesstransceivers 712 and 714, performed by the control unit 734, will now bedescribed in detail.

The control unit 734, based on information related to the receivedinformation about the wireless transceivers 712 and 714, determineswhether coverage values corresponding to the wireless transceivers 712and 714 are present. That is, the control unit 734 determines thatcoverage values of the wireless transceivers 712 and 714 correspondingto unique information about the wireless transceivers 712 and 714 arepresent in the storage unit 736. If the coverage values of the wirelesstransceivers 712 and 714 are not present in the storage unit 736, thecontrol unit 734 determines a coverage region according to a measuredsignal strength and generates a corresponding coverage value and storesthe coverage value in the storage unit 736.

The control unit 734 changes a coverage value according to strengths ofsignals transmitted by the wireless transceivers 712 and 714 such thatcoverage regions of the wireless transceivers 712 and 714 do not overlapwith coverage regions of other wireless transceivers. The control unit734 compares the measured signal strength of the wireless transceivers712 and 714 with a previously set reference signal strength and changesa coverage value in correspondence to a result of the comparison. Forexample, if the received signal strengths of transmission signals of thewireless transceivers 712 and 714, which are measured by the externaldevice 720 where the external device 720 is currently located, are lessthan a previously set reference signal strength, the coverage regionsare substantially smaller than a set reference coverage region. Thus,the control unit 734 needs to decrease the size of the referencecoverage region.

That is, the control unit 734 changes a coverage region according to asignal strength difference and changes a coverage value according to thechanged coverage region and stores the coverage value in the storageunit 736, such that coverage regions of the wireless transceivers 712and 714 do not overlap with each other. This allows the external device720 to receive signals transmitted by an appropriate wirelesstransceiver. The control unit 734 changes a coverage value such thatcoverage regions of the wireless transceivers 712 and 714 overlap witheach other and other wireless transceivers do not overlap each other,based on a policy. If the control unit 734 generates a coverage valuedue to the absence of coverage values of the wireless transceivers 712and 714, it is possible that the generated coverage region may overlapwith a coverage region of another wireless transceiver. In this case,the control unit 734 may reset the coverage region to prevent theoverlapping in the same manner as described above and may change acoverage value in correspondence to the reset coverage region.

The control unit 734 controls signal strengths of the wirelesstransceivers 712 and 714 based on the changed coverage value. Each ofthe wireless transceivers 712 and 714 includes an interface capable ofcontrolling a signal strength. The control unit 734 may transmitinformation about the changed coverage value to the wirelesstransceivers 712 and 714 through the external device 720, or maydirectly transmit the information to the wireless transceivers 712 and714. Thereafter, each of the wireless transceivers 712 and 714 controlsa transmission signal strength in correspondence to the changed coveragevalue.

The method of controlling coverage of a wireless transceiver describedabove may be embodied as a computer-readable code on a non-transitorycomputer-readable recording medium, which may be any type of recordingdevice storing data that is readable by a computer. Examples of therecording medium include Read-Only Memory (ROM), Random Access Memory(RAM), CD-ROMs, magnetic tapes, floppy disks, and optical data storagedevices. The computer-readable recording medium can also be distributedover a network of coupled computer systems so that the computer-readablecode is stored and executed in a decentralized fashion. Functionprograms, code, and code segments for implementing the service methodmay be easily derived by programmers of ordinary skill in the art.

While the present invention has been particularly shown and describedwith reference to embodiments thereof, it will be understood by those ofordinary skill in the art that various changes in form and details maybe made therein without departing from the spirit and scope of thepresent invention as defined by the following claims. Accordingly, thedisclosed embodiments should be considered in an illustrative senserather than in a limiting sense. The scope of the present invention isdefined not by the detailed description of the present invention but bythe appended claims, and all differences within the scope will beconstrued as being included in the present invention.

What is claimed is:
 1. A method of controlling coverage of a wirelesstransceiver, the method comprising: receiving information about thewireless transceiver from an external device; and changing a presetcoverage value of the wireless transceiver based on the receivedinformation about the wireless transceiver.
 2. The method of claim 1,wherein the information about the wireless transceiver comprises uniqueinformation of the wireless transceiver and signal strength informationabout the wireless transceiver which is detected by the external device.3. The method of claim 2, wherein the information about the wirelesstransceiver further comprises location information about the externaldevice.
 4. The method of claim 3, wherein the location information aboutthe external device is Global Positioning System (GPS) information aboutthe external device.
 5. The method of claim 1, wherein the coveragevalue of the wireless transceiver is changed in such a manner that acoverage region of the wireless transceiver does not overlap with acoverage region of another wireless transceiver.
 6. The method of claim1, further comprising generating a coverage value of the wirelesstransceiver based on the received information about the wirelesstransceiver, when a previously stored coverage value of the wirelesstransceiver is not present.
 7. The method of claim 1, further comprisingchanging a signal strength of the wireless transceiver based on achanged coverage value.
 8. The method of claim 1, further comprisingtransmitting information about the wireless transceiver having a changedcoverage value to an external device.
 9. The method of claim 1, whereinthe wireless transceiver is an access point.
 10. An apparatus forcontrolling coverage of a wireless transceiver, the apparatuscomprising: a communication unit that receives information about thewireless transceiver from an external device; and a control unit thatchanges a coverage value of the wireless transceiver based on thereceived information about the wireless transceiver.
 11. The apparatusof claim 10, wherein the information about the wireless transceivercomprises unique information of the wireless transceiver and signalstrength information about the wireless transceiver, which signalstrength information is detected by the external device.
 12. Theapparatus of claim 11, wherein the information about the wirelesstransceiver further comprises location information about the externaldevice.
 13. The apparatus of claim 12, wherein the location informationabout the external device is Global Positioning System (GPS) informationabout the external device.
 14. The apparatus of claim 10, wherein thecontrol unit changes the coverage value such that a coverage region ofthe wireless transceiver does not overlap with a coverage region ofanother wireless transceiver.
 15. The apparatus of claim 10, wherein thecontrol unit generates a coverage value of the wireless transceiverbased on the received information about the wireless transceiver, when apreviously stored coverage value of the wireless transceiver is notpresent.
 16. The apparatus of claim 10, wherein the control unitcontrols a signal strength of the wireless transceiver based on achanged coverage value.
 17. The apparatus of claim 10, wherein thecommunication unit transmits information about the wireless transceiverhaving a changed coverage value to an external device.
 18. The apparatusof claim 10, wherein the wireless transceiver is an access point.
 19. Anon-transitory computer readable recording medium having recordedthereon a program for executing a method of controlling coverage of awireless transceiver, the method comprising: receiving information aboutthe wireless transceiver from an external device; and changing a presetcoverage value of the wireless transceiver based on the receivedinformation about the wireless transceiver.